A political figure backed by the party is in a tight race for a Senate nomination

Few places in America have a stronger Republican establishment than Wisconsin. But in the Trump-era politics of disruption, the backing of the party and its bigwigs may not be enough.

Ahead of Tuesday’s Senate GOP primary, state Sen. Leah Vukmir, a longtime ally of Gov. Scott Walker, has all the endorsements that in years past would have made her a shoo-in. But her denunciation of President Trump during the 2016 presidential primary has drawn attacks from her opponent, Marine veteran Kevin Nicholson, a former active Democrat...

RELATED VIDEO

Three Important Senate Races to Watch in November

The Senate is currently split with 51 Republicans and 49 Democrats. WSJ's Gerald F. Seib looks at three important Senate races to watch during the midterm elections. Photo: AP